Durable textile soil release agent

ABSTRACT

A polyol N-methylol-amino plast composition containing an oxyalkylated phosphoric acid is provided which confers improved soil release properties on cellulosic fibers and blends of cellulosic fibers with polyester fibers having durable press or wash and wear characteristics.

United States Patent 1 i 1 1 54,859

Doerr Aug. 28, 1973 [54] DURABLE TEXTILE SOIL RELEASE AGENT 3,416,952 12/1968 lgiclmyre ellal. 8/l81/5.7 X 3,654,244 4/1972 ittman et 115.7 [75] Invent Rich'rd Orange 3,676,052 7/1972 Harper et a1 8/1 15.6 [73] Assignee: Olin Corporation, New Haven, 3.375,305 3/l968 Patton et a1. 260/982 v FOREIGN PATENTS OR APPLICATIONS [22] 1 1972 1,036,999 7/1966 Great Britain 21 Appl. No.: 260,534

Related US. Application D t Primary Examiner-Char1es E. Van Horn [62] Division of Set. No. 91,214, Nov. 19, 1920, 45mm 'f abandone 1 vAttorney-Thomas P. 0 Day [52] U.S. Cl. 8/ll5.6, 8/1 15.7, 8/116 P,

8/182, 8/183, 8/185, 8/186, 8/187, 8/DIG. H, ABSTRACT [51] I t Cl 1 3 3: ?2; ;6 E: A polyol N-methylol-amino plast composition contain- [58] i 2 3 15 1 l5 7 ing an oxyalkylated phosphoric acid is provided which e o confers improved soil release properties on cellulosic 8,116 187 fibers and blends of cellulosic fibers with polyester fibers having durable press or wash and wear character- 5 References Cited i UNITED STATES PATENTS 3,407,026 10/1968 Mauldin 8/1 15.6 Claims; N0 Drawings 1 DURABLE TEXTILE SOIL RELEASE AGENT This is a division of co-pending application Ser. No. 91,214 filed Nov. 19, 1970, now abandoned.

This invention relates to novel textile treating compositions, the method of preparing and applying such compositions and to textile materials treated therewith. More specifically the invention relates to compositions and textile treatments which provide improved soil release properties to textiles. I

Cellulosic fibers including cotton, linen, jute, flax and regenerated cellulose fibers, including viscose rayon, in the form of staple, yarn and fibers have generally satisfactory soil release properties.

The term soil release refers to the ability of the fibers to be washed to remove solid and particularly oily materials in contact with said fibers and renders fibers more amenable to cleansing by washing.

A further feature of the present invention is the prevention of soil redeposition from the wash water. During washing and rinsing, the soil has a tendency to'redeposit on the fibers from the wash water or rinse water. The soil release ability of fibers treated according to the present invention prevents redeposition of soil removed in the washing.

The introduction of blends of cotton with synthetic fibers has aggravated the problem of soil release and redeposition. The synthetic fibers, particularly the polyester fibers, for example, those prepared from poly(ethylene terephthalate), have many desirable properties which have made themcommercially acceptable for many end uses, both alone and in various combinations with natural fibers. However, the soil release properties of the polyester fibers are much poorer than those of the cellulosic fibers. The polyester fibers are hydrophobic rather than hydrophilic. They attract and hold the soil more tenaciously than cellulosic fibers and hinder the ingress of water necessary for cleaning the fabric.' 1

The problem of soil release and redeposition has been further compounded by durable press and washand-wear treatments which render the cellulosic fibers in textiles and blends less hydrophilic. These finishing treatments usually consist of impregnating and reacting the cellulosic fibers with aminoplast resin having N- methylol groups. The fibers subjected to such treatments retain the soil more tenaciously than the untreated, cellulosic fibers, lose much of their soil release properties and are more subject fo redeposition of soil. Oily soils accepted and retained by garments of these fibers, when worn, are difficult to remove in normal washing machine operations. Even relatively clean garments containing these treated fibers tend to pick-up soil from the dirty wash water. As a result, oily soil spots are never completely removed from these garments by washing. Repeated washings intensify the effects of soil pick-up from the dirty wash water with increasing overall grey or yellow discoloration. Eventually the garment becomes unsightly before it is worn out. i

Soil release agents presently available do not provide fibers with adequate levels of initial and durable soil release properties when the fibers have been subjected to durable press or wash-and-wear finishing.

Present soil release agents based on polymeric derivatives of acrylic acid are disclosed, for example, in U.S. Pat. No. 3,090,704 directed to a methyl methacrylatesodium styrene sulfonate-glycidol methacrylate terpolymer and U.S. Pat..No. 3,377,249 directed to a process in which the active soil release agent is a copolymer of ethyl acrylate and acrylic acid in a :30 ratio. Problems which still remain when known soil release agents are used with cellulosic textiles, including blends with polyesters, which have been finished with aminoplast resins include:

1. Unsatisfactory, initial soil release effect.

2. Poor durability of soil release properties to repeated washings.

3. Poor compatibility with the magnesium chloride or zinc nitrate catalysts commonly used in aminoplast resin finishing compositions.

4. Require a two-bath process instead of a single bath application for best results.

5. Acrylate emulsions tend to precipitate on standing.

Some have poor freeze-thaw stability.

6. Acrylate soil release emulsions tend to form gritty deposits on fabric pad rolls during application which causes problems when picked off by the fab- The present invention is primarily directed to the treatment of cellulosic fabrics and to fabrics containing a substantial portion of synthetic polyester fibers. These fibers'are generally formed into fabrics which are knitted, woven or non-woven. However, the advantages of this invention can be achieved by treating the fibers, yarns, or threads employed to produce these fabrics. Moreover, and more specifically, the process of the present invention is preferably used for treating textile materials containing cellulosic fibers or blends of polyester and cellulosic fibers to confer durable press or minimum care characteristics and improved soil release properties. The fabrics are suitably formed from a mixture of polyester, e.g.', poly(ethylene terephthalate) fibers and cotton or rayon fibers. Textile materials containing only cellulosic fibers are also within the scope of the present invention.

Surprisingly, it has now been discovered that the above mentioned problems and deficiences are substantially eliminated by combining certain oxyalkylated phosphoric acid polyols with N-methylol aminoplast textile resin and a suitable catalyst, applying the mixture to the textile and subjecting the treated textile to resin curing conditions. The invention contemplates the finishing compositions combining the oxyalkylated phosphoric acid polyol and the aminoplast resin, catalyzed and uncatalyzed, the process of treating fibers with the finishing composition and the fibers and textiles thus treated. I

Advantages of the present invention are:

1. An improved level of initial soil release effect on treated fabric.

2. An improved level of durable soil release effect on treated fabric after multiple washings.

3. improved compatibility with the magnesium chloride and zinc nitrate textile resin catalysts commonly used in N-methylol aminoplast formulations.

4. A single bath process that increases rate of production and is more economical that a two-bath process. I

5. A completely homogeneous watersoluble finishing composition not subject to separation of freezethaw instability.

6. No undesirable product build-up on fabric pad rolls during application. a

The oxyalkylated phosphoric acid soil release agent is prepared by oxyalkylating 100 percent phosphoric acid with 8 or more moles of alkylene oxide, suitably propylene oxide or mixtures containing at least 20 percent by weight of propylene oxide, balance alkylene oxides having two to four carbons. Satisfactory results hve been obtained using polyols having molar ratios of alkylene oxide to phosphorus (or phosphoric acid) or 40:1 or more. With propylene oxide as the sole alkylene oxide, especially advantageous results are obtained using a ratio of from 8:1 to 12:1.

Minor amounts, from 2 to 25 percent by weight of the alkylene oxide mixture is suitably other alkylene oxides of two to four carbons, for example, alphaor beta-butylene oxide, trichlorobutylene oxide, glycidol and epichlorohydrin. The oxides are suitably reacted with 100 percent phosphoric acid in block type as well as random type polymers.

The resulting polyols are used with textile treating resins, suitably N-methylol aminoplasts, for example, N-methylol urea-formaldehyde, N-methylol melamine, N-methylol alkyl carbamates and N-methylol cyclic urea-formaldehyde, e.g., dihydroxy dimethylol ethyleneurea resins. Formulations usually contain about 2 to 30 percent of the resin and also other conventional components. The porportion of polyol added is suitably about 2 to percent based on the total weight of the formulation.

Catalysts usually added to these resins are metal salts of the formula MX,, where M is magnesium or zinc and X is chloride or nitrate, particularly, magnesium chloride or zinc nitrate. Usually from 1 to 15 percent of the catalyst based on the weight of the resin is suitable.

In use, the mixture of polyols and aminoplast, including catalyst, is applied to the fibers or textile to be treated and cured under conditions usual for applying and curing the aminoplast finishing compositions, that is, at temperatures of about 300 to 400 F. for 0.1 to 15 minutes.

EXAMPLE I A. Preparation of 100 percent Phosphoric Acid Initiator for the polyol was 100 percent phosphoric acid prepared from commercial 105 percent phosphoric acid by the addition of one part of distilled water to 20.5 parts of 105 percent phosphoric acid. The water was added to the acid with agitation, maintaining the temperature of the mixture at 24 to 40 C. After the addition was completed, the mixture was heated at 85 C. for 2 hours.

B. Preparation of Polyol The 100 percent phosphoric acid prepared in Example LA. was oxyalkylated in a 100 gallon reactor formed of 304 stainless steel fitted with an agitator and equipped to add the alkylene oxide below the surface of the liquid in the reactor under nitrogen padding and with external ice water cooling. Both acid feed and oxide feed were introduced into the reactor under nitrogen pressure through flow meters and check valves.

The reactor initially contained 12 pounds of finished product from a previous batch. The feed of propylene oxide was started and a weight ratio of propylene oxide to phosphoric acid of at least 5:1 was maintained. The rates of addition of acid and oxide were adjusted to maintain the reaction temperature at to 30 C. AFter the additionwas completed, the reaction mixture was stirred at 25 to C. for 6 hours. The reaction mixture was then purged with a stream of dry nitrogen and refluxed for 4 hours at 54 C. Excess oxide was allowed to escape and the reflux temperature to rise to C. This temperature was maintained for 4 hours and the mixture was finally stripped at 70 C. under 10 mm. Hg pressure.

To 200 grams of the above polyol was added 0.5 ml.-

of 48 percent BF etherate with good agitation. The system was padded with dry nitrogen and propylene oxide was introduced, allowing the reaction temperature to rise to 70 to C. under reflux. When the reaction temperature began to fall, the addition of propylene oxide was discontinued and refluxing was continued for 1 hour at 70 to 75 C. The mixture was stripped at 70 to 75 C. under 10 mm. Hg pressure for 1 hour and then cooled to room temperature. The oxyalkylated phosphoric acid polyol product had a molar ratio of propylene oxide to phosphoric acid of 9.75:1. C. Formulation Preparation Five grams of the product from Example 1.8. was weighed into a 250 ml. beaker and dissolved in 19 grams of distilled water. To the solution was added 13 grams of Permafresh LE, a dimethylol cyclic urea compound, 1 gram of Polymel CC," a polyethylene emulsion softener and 5 grams of 20 percent by weight aqueous magnesium chloride solution. The final formulation had a pH of 5.9. D. Formulation Application A 5 inches X 8 inches swatch of 65/35 Dacron/cotton shirting fabric was thoroughly wetted in the formulation prepared in Example I. C; Excess solution was removed from fabric bypassing the open width through pressurized squeeze rolls to give approximately 60 percent wet pick-up of the formulation on the dry weight of the goods. The impregnated fabric was dried at 1 10 to C. for 90 seconds and then cured at 159 to 161. C. for seconds. E. Soil, Release Evaluation The cured fabric, after 30 minutes at ambient temperature and humidity, was soiled with 10 drops of dirty motor oil centrally distributed over a 2 to 4 square inch area. The oil was allowed to soak into the fabric for 30 minutes and then it was washed in a Tergotometer at 50 to 55 C. for 20 minutes using 1.5 grams of Tide in 1 liter of water. The washed fabric was rinsed in warm water and dried on a line. The dried fabric was rated for soil release visually by placing the sample on a white cardboard background and observing the color intensity of any remaining dirty motor oil soil. The fabric of this example gave complete soil release of the dirty motor oil. The same type of fabric finished with 10 percent "Rhoplex SR-488", a commercial acrylic type soil release agent, in a conventional two-bath application and soiled and washed in the previously described manner, did not give complete soil release of dirty motor oil. The soiled area was clearly visible after washing. Other portions of the same fabrics washed prior to soiling still show the superior soil release properties of the product of this invention applied in a single bath over Rhoplex SR-488 applied by a two-bath application.

Initial soil'release was also measured on cloth which was treated as described with the resin-polyol composition, cured and, without washing, was soiled and washed once. The reflectance was 58. Durable soil release was measured on cloth which was resin-polyol treated, cured and washed five times, soiled and washed once. Reflectance was 61, showingexcellent durability. The same treatment with the same resin but omitting the oxypropylated phosphoric acid polyol resulted in a value of 33 for both initial and durable soil C. and D. Formulation Preparation and Application The polyol thus prepared was formulated and applied to shirting as described in Example II.C. and D.

E. Soil Release Evaluation release. 5 The soil release properties of the formulation thus prepared and applied were measured as described in EXAMPLE n Example LE. The results in Table I show excellent soil A. and B. Preparation of Polyol release and excellent durability. The procedure of Example LA. and B. was repeated TABLE I at a reaction temperature of 60 to 70 C., the post re- 10 action temperature was 70 to 75 C. for 2 hours and Use hlziluebliefltectzige- Le e um w e the stripping was carried out at 70 to 75 C. under 10 Initial l {6 25 30 to 15 mm. Hg pressure for 2 hours. The molar ratio of 2 5a 57 5a 57 57 53 r 4 69 68 67 65 64 53 oxide to phosphoric acid was 10.1.1 in the product. 6 72 68 69 69 66 50 C. Formulation Preparation 15 8 72 63 69 68 64 59 The product of Example ILA. and B. was formulated i0 75 7o 59 70 5s 5a in distilled water at percent by weight use level with :i z; 23 2g 2; 26 percent Aerotex Resin EU, an N-methylol cyclic I6 79 73 69 70 70 54 urea-formaldehyde resin, 2 percent magnesium chloride, and 1 percent of Cyanatex HP softener, a blend 2 EXAMPLES lv'xm of fatty acid esters. Polyols containing mixed oxides were prepared by D. Formulation Application r the procedure of Example llI.A. and B. using the pro- A 5 inches by 8 inches swatch of 65/35 Dacron/cotportions of propylene oxide (P0) and ethylene oxide ton shirting was thoroughly wetted in the formulation (E0) indicated in Table II. The various polyol products prepared in Example ILC. Excesssolution was removed 25 were formulated, the formulation was applied and the from the fabric by passing the opened width through soil release properties were measured as described in pressurized rubber squeeze rollsto give approximately Example I.C., D. and E. The properties of the polyols 80 percent wet pick up of the formulation on the dry and the soil release properties are shown in Table II. weight of the'goods. The impregnated fabric was dried These results show excellent soil release and excellent at 110 to 120 C. for 9 0 seconds and then cured at durability.

' TABLE 11 Polyol preparation Wt. pet. Blue reflectors, number of washes Order of Example No. Type addition PO E0 wt. Ratio Initial 1 5 10 15 iv Block 120-130 75 585 9.1 59 55 55 57 54 5s v .do Po-Eo 25 75 1,400 27.8 58 58 5s 50 58 v1... 75 25 532 9.95 51 55 55 59 57 VII. 1,520 52.5 49 52 55 52 54 52 VIII. 500 7.5 50 5s 5s 54 59 50 1x... 925 15.5 59 as as 55 57 55 x 1,550 27.2 49 55 54 52 53 52 XI... 525 9.1 50 52 54 54 55 XIL. 950 18.4 58 53 53 57 57.5 x111 do 25 75 1,744 35.1 55 51 54 54 52 Untreated cloth 54 54 53 53 53 42 Resin of Example I alone; no polyol 52 45 49 49 46 43 I Molar ratio of oxides:phosphorus.

wash 71 10 washes 67 20 washes 68 25 washes 67 30 washes -59 The above soil release value showed excellent durability.

EXAMPLE III A. and B. Preparation of Polyol To 33 grams of 100 percent phosphoric acid was added 0.2 ml. of 48 percent BF etherate and 187 grams of propylene oxide was introduced as described in Example 1.8. The reaction temperature was 70 to 80 C. under total reflux. The time of addition was 1 hour and the resulting mixture was maintained at 70 to 80 C. for 3 hours. The mixture was stripped at 70 to 80 C. under l5 to 20 mm. Hg pressure for 1 hour. The resulting polyol had a molar ratio of oxide to phosphorus of 8.2:1.

What is claimed is:

1. Method of treating cellulosic fibers by impregnating said fibers with an aqueous mixture of N-methylol aminoplast resin and from 2 to 20 percent, based on the total weight of the formulation, of oxyalkylated phosphoric acid wherein the alkylene oxide moiety is selected from the group consisting of propylene oxide and mixtures containing at least 20 percent by weight of propylene oxide, balance alkylene oxide having two to four carbons, the'molar ratio of said alkylene oxide moiety to the phosphoric acid moiety being at least 8: I; said mixture having incorporated therein an aminoplast resin curing catalyst of the formula MK where M is selected from the group consisting of magnesium and zinc and V is selected from the vgroup consisting of chloride and nitrate and mixtures thereof, said catalyst amounting to l to 15 percent by weight based on said aminoplast resin; and curing to produce cellulosic fibers having a durable finish with improved soil release properties.

2. Method as claimed in claim 1 in which said curing is carried out by heating at from 300 to. 400 F. for 0.1

7 8 to minutes. 5. Method as claimed in claim 1 in which said alkyl- 3. Method as claimed in claim 1 in which said resin ene oxide is propylene oxide and said ratio is from 8:1 is selected from the group consisting of N-methylol to 12:1. u r y N-methylol m e, -methylol 6. A textile containing from 10 to 100 percent of celalkyl carbamate and N-methylol cyclic urea- 5 lulosic fibers, balance polyester fibers, wherein said formaldehyde resins. cellulosic fibers are the product of the process of claim 4. Method as claimed in claim 1 in which said molar 1,

ratioisfrom 8:1 to40zl. r a: 

2. Method as claimed in claim 1 in which said curing is carried out by heating at from 300* to 400* F. for 0.1 to 15 minutes.
 3. Method as claimed in claim 1 in which said resin is selected from the group consisting of N-methylol urea-formaldehyde, N-methylol melamine, N-methylol alkyl carbamate and N-methylol cyclic urea-formaldehyde resins.
 4. Method as claimed in claim 1 in which said molar ratio is from 8:1 to 40:1.
 5. Method as claimed in claim 1 in which said alkylene oxide is propylene oxide and said ratio is from 8:1 to 12:1.
 6. A textile containing from 10 to 100 percent of cellulosic fibers, balance polyester fibers, wherein said cellulosic fibers are the product of the process of claim
 1. 